1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
|
// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
//
// This include file determines how BlockSet is implemented.
//
#ifndef _BLOCKSET_INCLUDED_
#define _BLOCKSET_INCLUDED_ 1
// A BlockSet is a set of BasicBlocks, represented by the BasicBlock number (bbNum).
// Unlike VARSET_TP, we only support a single implementation: the bitset "shortlong"
// implementation.
//
// Note that BasicBlocks in the JIT are numbered starting at 1. We always just waste the
// 0th bit to avoid having to do "bbNum - 1" calculations everywhere (at the BlockSet call
// sites). This makes reading the code easier, and avoids potential problems of forgetting
// to do a "- 1" somewhere.
//
// Basic blocks can be renumbered during compilation, so it is important to not mix
// BlockSets created before and after a renumbering. Every time the blocks are renumbered
// creates a different "epoch", during which the basic block numbers are stable.
#include "bitset.h"
#include "compilerbitsettraits.h"
#include "bitsetasshortlong.h"
class BlockSetOps : public BitSetOps</*BitSetType*/ BitSetShortLongRep,
/*Brand*/ BSShortLong,
/*Env*/ Compiler*,
/*BitSetTraits*/ BasicBlockBitSetTraits>
{
public:
// Specialize BlockSetOps::MakeFull(). Since we number basic blocks from one, we remove bit zero from
// the block set. Otherwise, IsEmpty() would never return true.
static BitSetShortLongRep MakeFull(Compiler* env)
{
BitSetShortLongRep retval;
// First, make a full set using the BitSetOps::MakeFull
retval = BitSetOps</*BitSetType*/ BitSetShortLongRep,
/*Brand*/ BSShortLong,
/*Env*/ Compiler*,
/*BitSetTraits*/ BasicBlockBitSetTraits>::MakeFull(env);
// Now, remove element zero, since we number basic blocks starting at one, and index the set with the
// basic block number. If we left this, then IsEmpty() would never return true.
BlockSetOps::RemoveElemD(env, retval, 0);
return retval;
}
};
typedef BitSetShortLongRep BlockSet;
// These types should be used as the types for BlockSet arguments and return values, respectively.
typedef BlockSetOps::ValArgType BlockSet_ValArg_T;
typedef BlockSetOps::RetValType BlockSet_ValRet_T;
// Initialize "_varName" to "_initVal." Copies contents, not references; if "_varName" is uninitialized, allocates a
// var set for it (using "_comp" for any necessary allocation), and copies the contents of "_initVal" into it.
#define BLOCKSET_INIT(_comp, _varName, _initVal) _varName(BlockSetOps::MakeCopy(_comp, _initVal))
// Initializes "_varName" to "_initVal", without copying: if "_initVal" is an indirect representation, copies its
// pointer into "_varName".
#define BLOCKSET_INIT_NOCOPY(_varName, _initVal) _varName(_initVal)
// The iterator pattern.
// Use this to initialize an iterator "_iterName" to iterate over a BlockSet "_blockSet".
// "_blockNum" will be an unsigned variable to which we assign the elements of "_blockSet".
#define BLOCKSET_ITER_INIT(_comp, _iterName, _blockSet, _blockNum) \
unsigned _blockNum = 0; \
BlockSetOps::Iter _iterName(_comp, _blockSet)
#endif // _BLOCKSET_INCLUDED_
|
